Field:
Various communication systems may benefit from appropriate representations of communication parameters and information. For example, certain wireless communication systems may benefit from packet number representation for multicast channel block error rate reporting.
Description of the Related Art:
Multimedia broadcast multicast service single frequency network (MBSFN) measurement for minimization of drive tests (MDT) can involve the issue of multicast channel (MCH) block error rate (BLER) reporting. MCH BLER reporting may be associated with number of MCH packets received during an L1 measurement period. The packet number may be reported to facilitate network evaluation/weighting of the reliability of the received BLER report. For example, if a reported BLER is 50% but there are only 4 MCH packets received by the UE, the network may simply ignore the BLER when adjusting the MBSFN transmission parameters based on MDT measurement. Moreover, for MCH BLER, the L1 measurement period may be the same as a logging interval configured via radio resource control (RRC) signaling. There a variety of possible ways to encode the packet number.
For this specific issue of MCH BLER reporting, the range of the possible packet numbers is 0 to 36864, and the range of the possible BLERs is 0.1% to 50%. If 5 bits are used for BLER encoding, 11 bits may be used for packet number encoding, thereby using 16 bits in total, which can fit into 2 octal digits.
With 11 bits and plain representation, the maximum value is 2048. This may not be enough to determine the reliability of small BLER values, and the most proper upper limit is around 10000. Alternatively, with 13 bits and plain representation, the maximum value is 8192. However, 13 bits correspond to 3 octal digits, thus providing a larger signaling overhead than the 11-bit approach. Another option may be a floating representation with an 8-bit mantissa and a 3-bit exponent. The maximum number that can be represented with this number format is 255×128=32640. However, there are many overlapping states with this representation (i.e. multiple different bit presentations will encode the same number).